Bifunctional of Fe3O4@chitosan nanocomposite as a clarifying agent and cationic flocculant on different sugar solutions as a comprehensive semi industrial application

In the sugar industry, eliminating side impurities throughout the manufacturing process is the most significant obstacle to clarifying sugar solutions. Herein, magnetic chitosan (MCS) nanocomposite was Fabricated to be used as a biodegradable, environmentally friendly clarifying agent throughout the cane juice and sugar refining processes. Fe3O4 was synthesized using the coprecipitation procedure, and then MCS was combined using a cross-linking agent. Furthermore, 14.76 emu g−1 was the maximum saturation magnetization (Ms) value. Because MCS is magnetically saturated, it may be possible to employ an external magnetic field to separate the contaminant deposited on its surface. Additionally, zeta potential analysis showed outstanding findings for MCS with a maximum value of (+) 20.7 mV, with improvement in color removal % up to 44.8% using MCS with more than 24% in color removal % compared to the traditional clarification process. Moreover, utilizing MCS reduced turbidity from 167 to 1 IU. Overall, we determined that MCS nanocomposite exhibits considerable effectiveness in the clarifying process for different sugar solutions, performing as an eco-friendly bio-sorbent and flocculating material.

www.nature.com/scientificreports/Polyacrylamide is the most widely used flocculant in the sugar industry to improve separation during the clarification process, refineries that use the phosphatation process to improve the separation of calcium precipitates from the sugar solution, and the production of raw sugar.Studies and research on the topic of sugar solution flocculation would serve as the foundation for studies on the usage of polyelectrolytes to improve color removal in the sugar industry processes 11,12 .
Due to its low cost, availability, abundance, biodegradability, biocompatibility, nontoxicity, and high adsorption capacity for its ability to remove organic pollutants from wastewater, chitosan (CS) and its derivatives have attracted a lot of interest.However, they have substantial drawbacks that limit their effectiveness in the adsorption process, such as poor mechanical characteristics, weak acid stability, low surface area, low porosity, and low temperature resistance 10 .
Chitosan can be combined with other substances to create composite adsorbents, which is an excellent way to get around some of the disadvantages of chitosan and enhance its adsorption capacity 10 .In general, ferromagnetic materials, alloys, oxides, or composite structures based on iron, cobalt, and nickel are referred to as magnetic particles.The most prevalent and widely used type of naturally occurring iron oxide is magnetite, which has the chemical formula Fe 3 O 4   13   .The ferrous ions occupy half of the octahedral lattice sites, ferric ions occupy the other half, and all of the tetrahedral lattice sites, defining its crystalline cubic inverse spinel structure 14 .A chitosan polymer matrix and a dispersed phase containing magnetic particles make up a magnetic chitosan composite (MCS).
As a result of its important biological and chemical characteristics, chitosan has undergone extensive research as a foundation material for magnetic carriers.Recent years have seen a surge in interest in MCS due to its better performance, which has led to substantial study into the production and use of these materials in several scientific domains 12,15 .MCS materials have a wide range of biomedical, environmental, and analytical applications in the biomedical, environmental, and analytical fields, including applications for enzyme-based biofuel cells, anticancer embolotherapy, targeting drug carriers, artificial muscle, bone regeneration, and fluorescence probes 16 .Additionally, MCS is frequently employed in the processes of clarifying sugar and treating wastewater 17 .MCS has a high adsorption capacity and a quick adsorption rate compared to other adsorbents, even at low concentrations and rapid equilibrium durations.Chitosan-based adsorbents can be challenging to remove from the aqueous solution after adsorption using conventional separation techniques like filtration and sedimentation because adsorbents may clog filters or be lost.
Recent research has concentrated on magnetic separation technology to address issues with the simplicity of separation and regeneration of adsorbents.An alternate technique for treating water and wastewater that has recently drawn a lot of attention is separation technology using magnetic adsorbents 18,19 .In the 1970s and 1980s, scientists started to realize that magnetic materials may be used to separate metal contaminants from various matrices that are magnetic field sensitive.MCS are primarily made of an inorganic metal oxide and chitosan organic material.Chitosan generally lacks magnetic characteristics, so for the particles to perform best in particle separation, a separate magnetic component must be introduced 19 .

Preparation of MCS nanocomposite
Magnetic chitosan nanocomposite was fabricated using the coprecipitation method and cross-linking agent.Firstly, 50 mL of distilled water was added to 4 g of FeCl 3 •6H 2 O and 3 g of FeSO 4 •7H 2 O, then the mixture was stirred for 10 min while raising the temperature to 70 °C, after that 2 M of ammonium hydroxide solution was slowly dripped into the mixture until forming magnetite (Fe 3 O 4 ) as shown in Fig. 1.Subsequently, 10 g of chitosan was added to 1 L of 1% (v/v) acetic acid solution and stirred on a magnetic stirrer for 22 h at 800 rpm until chitosan was completely dissolved.After that, the formed magnetite was added to the chitosan solution under stirring for another 12 h to obtain a uniform homogenous suspension.Then 5 mL of epichlorohydrin was added dropwise to avoid the formation of big bulk colloidal precipitation until the crosslink was performed for MCS as shown in Fig. 1.

Semi-industrial application
Studying the impact of MCS nanocomposite on flocculation and color removal requires utilizing the phosoflotation (phosphatation followed by flotation) process in the case of sugar syrup, and the traditional phosphatation process in the case of sugar juice.Our experiments were conducted at Quos Pilot Plant in Egypt and were designed to study the effect of MCS nanocomposite on both flocculation and color removal, as well as identify the best conditions for the clarification process.The semi-industrial experiment design was scientifically proposed by Eggleston at Audubon Sugar Institute 20 .Firstly, for sugarcane juice, 60 L of mixed juice (MJ) were first transported from the plant and divided into three reaction tanks (20 L/tank), which were then heated to 75 °C to begin the clarifying process as follows: (i) traditional phosphatation (control sample) and (ii) traditional phosphatation with MCS nanocomposite.Samples were separately added to reaction tanks with identical conditions, 5% H 3 PO 4 (300 ppm P 2 O 5 ), and Ca(OH) 2 baume (6) until the pH was 7.3 ± 0.1.The temperature is then increased until flashing at 103 °C before the anionic flocculant is added (dosage: 4 ppm).After the flocs had finally settled in the clarifier (retention time: 1 h), samples of clear juice (CJ) were taken for the testing of quality parameters.
Secondly, for sugar syrup, under the same conditions, 60 L of sugar syrup was made at 62 ± 1 °Brix and divided into three reaction tanks (20 L each tank).Once the temperature reached 80 °C, 480 mL of 5% H 3 PO 4 (~ 350 ppm P 2 O 5 ) and 400 mL of Ca(OH) 2 baume (6) were added, respectively, until the pH reached 7.1 ± 0.1, which corresponded to the control sample.After that, the synthesized nanocomposite was added to the respective tank (dose = 200 ppm), followed by the flotation process using the aeration pump for 30 s, and the addition of 140 mL of an anionic flocculant (dose 10 ppm).The flocs were then allowed to float for approximately 25 min, after which the samples of clear syrup were collected for investigation of quality parameters.

Analysis and instrumentations
The crystalline structure of each material and its composite were determined by powder X-ray diffraction (XRD) which was recorded using Philips diffractometer (Model PW 2103, λ = 1.5418Å, 35 kV and 20 mA) to obtain the crystal structures of the material in the 2θ region at 10° to 70°.Fourier Transform Infrared spectra (FT-IR) were measured using a Shimadzu-470 spectrophotometer, in the wavenumber range of 400-4000 cm −1 using KBr tablet to assign different functional groups contained in the synthesized samples.The morphological properties and compositions of CS and MCS nanocomposite were studied using Scanning Electron Microscope (SEM) and imaging was carried out using JSM T200 (JEOL, Japan) to observe the surface configuration and morphologies.Transmission Electron Microscope (TEM) and imaging was carried out using JEM 100 CXII (JEOL, Japan).Vibratory sample magnetometer (VSM, Lakeshore 7410) was carried out at room temperature using a vibrating sample magnetometer equipped with 2T magnet and under an applied magnetic field of 20 kOe to obtain the magnetic properties of the samples.Thermogravimetric analysis (TGA) was carried out using (Shimadzu DTG-60H, Japan) to investigate the thermal stability of MCS composite.Zeta potentials and particle size distribution of CS and MCS were determined by using a zeta potential and nanoparticle analyzer (Nano-ZS90X, Malvern, England).The compositions on the surface of MCS were analyzed by using an X-ray photoelectron spectroscopy (XPS), K-Alpha (Thermo Fisher Scientific, USA) with monochromatic X-ray AI K-alpha radiation -10 to 1350 e.v spot size 400 μm.Color absorbance was obtained using Jenway 7310 spectrophotometer.

SEM and TEM analyses
Every image was found to have a unique texture and morphology, as seen in Fig. 2a, which depicts the morphology of CS, which has certain protrusions on its surface 21 .As can be seen in Fig. 2b, SEM image of MCS reveals that the sample has nearly uniform grains of magnetite crystals on the surface of the chitosan, which display regular octahedrons with rough surfaces.The low-magnification SEM image suggests that it may be the result of magnetic iron oxide particles being embedded within the cross-linked chitosan.Further evidence linking www.nature.com/scientificreports/CS to microspheres relatively smooth surface suggests that the Fe 3 O 4 particles are tightly wrapped in chitosan polymers, preventing the magnetic carriers from dropping out 12 .A great number of slit pores can be seen on the MCS surface in the high-magnification SEM image as shown in Fig. 2c.In addition to being a material with a high surface area, its porous structure may provide more adsorption sites and enhancing MCS's capacity to adsorb anionic dyes in sugar solutions 22 .Nearly spherical and hexagonal nanoparticles with an average diameter of about 40 nm are visible in the sample's TEM image.Further proof that a core-shell and chain-like structure with good dispersion have successfully produced is provided by MCS nanocomposite 23 , as illustrated in Fig. 2d.Additionally, in conformity with SEM images, CS has been successfully coated onto the surface of the Fe 3 O 4 crystals.Also, a TEM picture revealed that the surface of MCS is made up of organized channels with hexagonal pore structures 24 .On the other hand, because of the nanometer-scale particle size, the adsorbents may have a large specific surface area.Similarly, the good dispersion of MCS nanocomposite can increase the surface area in contact with colorants substrate and contaminants, which will increase its adsorption capacity 25 .

FTIR analysis
As shown in Fig. 3a, pure Fe 3 O 4 nanoparticles, produce a distinctive peak at 560 cm −1 , which was attributed to the Fe-O stretching mode in the tetrahedral state of Fe 3 O 4

12
. The FTIR spectrum of MCS also exhibits the reflection of the typical peaks related to chitosan and Fe 3 O 4 nanoparticles, albeit with a small peak shift.In particular, there has been a shift in the peak at 620 cm −1 from 560 cm −1 , which corresponds to the stretching vibration of Fe-O.A further indication of the substantial interactions (such as metal coordination and hydrogen bonding) between the Fe 3 O 4 nanoparticles and chitosan during MCS formation is the shift of the peak corresponding to the stretching vibration of N-H 26 from 1660 to 1650 cm −1 .The MCS composite strengthened the typical peaks of -OH and -NH 2 at 2930 and 3400 cm −1 , respectively.The abundant polar groups in chitosan, notably -NH 2 and -OH, interacted polarly with the Fe-O bond and contributed to this outcome by encouraging the coupling of polar groups.The results of the FTIR spectra revealed that magnetic nanoparticles were coated with this polymer as a result of the precipitation interactions with chitosan 26 .

TGA analysis
Since the TGA is employed in order to determine the weight percentage of different components in composite particles and to assess the thermal stability of the composite.The TGA curves of Fe 3 O 4 , CS, and MCS are shown in Fig. 3b.The TGA thermogram of the MCS nanocomposite shows three separate weight losses and a thermal degradation profile that is comparable to that of chitosan.At temperatures between 100 and 150 °C, bound water vaporized, causing the initial stage of weight loss in MCS.The second stage, which exhibited significant weight loss, started at 200 °C and increased to 580 °C.The primary chain of chitosan molecules may have broken down as a result 27 .After 580 °C, the MCS's weightlessness started to balance progressively.Nevertheless, throughout the whole heating process (30-800 °C), Fe 3 O 4 showed excellent thermal stability and lost nearly little weight.Chelation between Fe 3+ and CS caused the reaction that linked Fe 3 O 4 and CS together 28 .Additional MCS bridging and structural modifications to CS increased CS thermal stability in MCS nanocomposite.The temperature at which www.nature.com/scientificreports/MCS finally decomposed was higher than the temperature at which pure CS decomposed.As a result, the Fe 3 O 4 nanoparticles have been successfully functionalized with chitosan groups, according to TGA thermogram data.

Zeta potential and particle size analyses
Figure 3c displayed the estimation of the surface charge of MCS and zeta potential measurements as a function of pH indicating a noteworthy value for the positive charge of MCS nanocomposite.The protonation of amine groups on the particle surface is thought to be the cause of the positive zeta potential that exists below the isoelectric point (pI).The zeta potential of MCS reduced when the pH level increased as shown in Fig. 3c.Amine groups were protonated and obtained a positive charge in the form of -NH 3 + at pH < 8.44, which is the isoelectric point (pI) for MCS.Thus at pH < 8.44, MCS demonstrated a positive potential.However, in the basic medium, a negative potential was seen at pH > 8.44.As a result, MCS was a modified adsorbent with the ability to adsorb cations in alkaline conditions and anions in an acidic environment 12 .The maximum value for the MCS nanocomposite was (+) 20.7 mV because the magnetite negative charge neutralized the charge of the quaternary ammonium group.Besides the material's ability to function as an adsorbent, the performance of the material in decolorization with anionic colorants is still obvious and promotes these interactions with quaternary ammonium groups of the nanocomposite.Additionally, the prepared MCS nanocomposite was assessed for its particle size as shown in Fig. 3d.According to results from transmission electron microscopy, the particle size distribution displayed a unimodal curve, with the majority sizes ranging from 350 to 620 nm and a cumulative distribution peak at 415 nm and a diameter of 44 nm 29 .

XRD analysis
Chitosan had typical semi-crystalline characteristics (110) at its diffraction peak at 23.1°, as illustrated in Fig. 4a.The cubic spinel structures of the pure Fe 3 O 4 particles had strong diffraction peaks at 30.28°, 35.62°, 43.3°, 53.8°, 57.4°, and 62.9°, which were consistent with the magnetite database 30 and corresponded to the various Fe 3 O 4 lattice planes (220), (311), (400), (422), (511), and (440), respectively.The relative intensity changed due to the change in the 2 signals in the XRD image of MCS.As an illustration, the peak at 20.13° was incredibly feeble, which may have been attributed to the quantity of chitosan supplied and the coprecipitation process of MCS 12 .The peaks splitting in MCS patterns at 40° and 80° are an indication of phase transformation that may be caused because of the dislocation in the crystal lattice of magnetite which confirms the formation of MCS nanocomposite.Additionally, both CS and Fe 3 O 4 crystalline characteristic peak intensity dropped, these findings indicated the formation of MCS.

Magnetization properties for MCS nanocomposite
Fe 3 O 4 can be added to the material to give it magnetic characteristics.For magnetic material recovery and reuse, magnetic characteristics are necessary, to evaluate the magnetic separation capability of MCS, magnetic strength could be employed 12 .As seen in Fig. 4b, the magnetic hysteresis loop of the MCS exhibited an S-like shape and overlapped.At room temperature, MCS had a maximum saturation magnetization (Ms) value of 14.76 emu g −1 .This finding was less than the value of 76.124 emu g −1 of pure Fe 3 O 4 due to the existence of non-magnetic CS www.nature.com/scientificreports/layers.The produced MCS sample may be recovered and separated from reaction media using an external magnetic field since it is magnetically saturated 31 .+ has a molar percentage of 7.97%, indicating a smaller positive value in the zeta potential analysis 27 .Furthermore, the Fe 3 O 4 lattice oxygen atoms, the oxygen atoms of OH groups from surface vacancies, and O-C=O, respectively, are responsible for the peaks at 529.88 eV, 532.66 eV, and 535.37 eV in the highresolution O1s spectra shown in Fig. 5e 10 .

Results of application
Throughout the whole process of producing sugar, colorants constitute a major problem because they have a negative effect on crystallization and affect the quality of white sugar 8,10 .Phosphatation, sulfitation, and carbonation are the traditional clarification processes used in Egyptian factories to produce white and refined white sugar because the main objective of the sugar clarification process is the separation of impurities and coloring matters from raw sugar syrup.This study compared the color removal percentage and turbidity of clarified juice and syrup obtained from each clarification method, traditional phosphatation clarification (control), traditional phosphatation clarification with CS, and traditional phosphatation clarification with MCS on both sugarcane juice and the raw sugar syrup.
The comparisons were done on a semi-industrial scale.Thus, the use of novel green biodegradable nanocomposite in the semi-industrial sugar clarifying process for both sugarcane juice and refined sugar will be covered in this section.

Evaluation of MCS nanocomposite on cane mixed juice (MJ)
The objective of this study is to improve the phosphatation clarification process efficiency by introducing a new green biodegradable clarifying agent.Accordingly, each case's quality parameters such as brix, purity, turbidity, dissolved solids (DS), and color removal % percentage will be evaluated in order to determine the effectiveness and impact of the new clarifying agent on the clarification process 20 .A comparison of the color removal percentage and turbidity was conducted on clear juice (CJ) was obtained from each clarification method as currently phosphatation clarification (control), currently phosphatation clarification with CS, and currently phosphatation clarification with MCS on Egyptian MJ.For more accurate evaluation three replicates were carried out at a pilot scale in Quos sugar factory, and for each trial average was calculated Due to an increase in active positive sites (quaternary amine) in the case of CS and its composites, as demonstrated in Fig. 6a, the color removal % increased to 8.7 and 17.1 using CS and MCS, respectively compared to the control sample (currently phosphatation clarification).Furthermore, the morphological shape and cavity sites that are present in MCS nanocomposite as shown in Fig. 2c, enhance to capture impurities and color materials by forming an insoluble matrix that is mostly the result of electrostatic attraction and may be improved by the tiny slots that are formed when CS and Fe 3 O 4 crosslink together 33 .As illustrated in Fig. 6b, it was demonstrated that applying MCS nanocomposite increased pH values compared to CS by itself since the protonated amine groups may interact electrostatically when the composites are formed via both inter and intra-molecule H-bonds 10 .The lower value of pH in CJ using CS and MCS nanocomposite is due to dissolving it in 1% acetic acid as presented in Table 1.While brix° and purity for CJ did not noticeably change while utilizing CS and MCS nanocomposite as shown in Fig. 6b.

Evaluation of MCS nanocomposite on sugar syrup
Here, the performance of the fabricated composite during the clarification process will also be evaluated by comparing the color removal percentage, turbidity, and flotation rate during the refining sugar process.Additionally, the clear syrup that was obtained was assessed using each of the following methods of clarification: currently phosphatation clarification (control) and currently phosphatation clarification with MCS on raw sugar syrup.Three replicates were conducted at pilot scale in Quos sugar factory, and each trial's average was determined.The color removal percentage utilizing MCS nanocomposite appears to have increased from 26.6 to 44.8% when compared to the control, as indicated in Fig. 6c.This increase can be attributed to the increased number of active sites (quaternary ammonium) as well as the channels and cavity structure previously discussed 34,35 .Furthermore, morphological shape results in the capture of impurities and the adsorption of coloring materials from the syrup in addition to a strong electrostatic interaction with the anionic colorants.Also, magnetic chitosan adsorbents are a great option for the decolorization process because of their facile magnetic separation and high chelating capacity 36 .Because of their larger specific surface area and porous shape, magnetic nanoparticles were used to construct the MCS nanocomposite adsorbent.In addition to the quaternarized ammonium groups that improve adsorption effectiveness, the protonation of FeOH to FeOH 2 + may also contribute to an increase in electrostatic attraction.As a result, as illustrated in Fig. 7, MCS nanocomposite possesses both the magnetization and adsorption characteristics that enable the separation of the adsorbates and their recovery from reaction environments using an external magnetic field.Furthermore, Fig. 6c demonstrated a 24.8% improvement in color removal percentage when using MCS compared to the control, demonstrating the greater efficiency of using this green nanocomposite as shown in Fig. S8.
On the other hand, the pH values for untreated syrup, treated syrup using the traditional clarification process, and treated syrup with the synthesized clarifying agent are displayed in Fig. 6d, and no noticeable changes were found.This is a positive sign since the change in pH value can lead to sugar inversion and turn it into reducing sugars resulting in the formation of additional coloring material and increased sucrose losses.Figure 6e demonstrates a notable reduction in turbidity from 167 IU for the untreated syrup to 14 IU for the control and 1 IU with MCS as mentioned in Table 2.In addition to their role as cationic color precipitant, these studies demonstrated that MCS possessed cationic flocculation efficiency that improved the anionic flocculant to capture impurities present in sugar syrup 37,38 as shown in Fig. S9.The performance of sugar syrup Brix° and purity before and after treatment is shown in Fig. 6d.The treated syrup using MCS showed a slight decrease in Brix° and purity values;  www.nature.com/scientificreports/this could be due to the strong electrostatic attraction between quaternary ammonium groups and coloring matters (soluble solids), as the zeta potential value for MCS nanocomposite is higher 39,40 .

Effect of flotation rate
Studying the flotation rate of cationic flocculant is a key factor, as it determines the retention time for syrup to discharge.It's also critical for increasing white sugar productivity while lowering operating expenses.Thus, to reduce the dose of anionic flocculant without negatively affecting the flocculation process, the flotation duration has been investigated in this case to validate the effectiveness of the MCS nanocomposite as a cationic flocculant.The mud volume percentage for the flocs at various intervals with varying doses of anionic flocculant is displayed in Table 3.As can be witnessed in Fig. 6f, the mud volume% without anionic flocculant (0 ppm) is larger than the others, with its negative charge, the anionic flocculant quickly attracted the cationic flocs, forcing them to float to the surface of the syrup.As a result, the mud volume percentage increases, as seen in Fig. S9.Following the addition of anionic flocculant dosage for 120 min, as indicated in Fig. S10, the flocs stabilized after a certain time  www.nature.com/scientificreports/and the volume became stable without obviously changing.We can see from the results in Table 3 and Fig. 6f that even at a 4 ppm dosage of anionic flocculant, the flocculation process is still as effective as the dosage is 12 ppm.

Conclusion
This study employed a new green clarifying agent as a cationic color precipitant and cationic flocculant in the clarification process.FTIR, XRD, and XPS investigations were used to confirm the formation of MCS nanocomposite.SEM and TEM images were used to highlight the morphological changes between the starting materials and the synthesized nanocomposite, ensuring that the green composite formed based on these changes in morphological forms.Additionally, the produced nanocomposite showed good thermal stability according to TGA study.Co-precipitation and cross-linking modification were used to synthesize MCS.Besides the chitosan amino group, the surface of MCS also included the crystal structure in the form of Fe 3 O 4 .As a type of paramagnetic material, MCS saturation magnetization was 14.76 emu g −1 .These findings showed that Fe 3 O 4 and chitosan had successfully modified MCS.The findings of the pilot-scale application demonstrated a notable increase in the percentage of color removal% when the synthesized nanocomposite was used instead of the traditional phosphatation method, which produced sulfur-less white sugar.

Figure 2 .
Figure 2. (a) SEM image for CS, (b) SEM image for MCS, and (c) TEM image for MCS.

Figure 3 .
Figure 3. (a) FT-IR spectra of CS, Fe 3 O 4 , and MCS nanocomposite, (b) Thermogravimetric curves for CS, Fe 3 O 4 , and MCS nanocomposite, (c) Zeta potential curves for CS and MCS nanocomposite, and (d) Particle size distribution of MCS nanocomposite.

A
substance's surface chemical state and element composition can be thoroughly studied with XPS.The five primary elements Cl, C, N, O, and Fe were represented by the XPS survey scan for MCS nanocomposite in Fig.5a, with signals of 200.64 eV, 288.23 eV, 402.26 eV, 534.13 eV, and 713.46 eV, respectively.The catalytic and magnetic properties of magnetite make it the most intriguing of the iron oxides.Surface reactivity and magnetism are denatured, and the crystal structure is changed from inverse spinel to spinel as a result of this reaction.Due to its sensitivity to Fe 2+ and Fe 3+ cations, X-ray photoelectron spectroscopy (XPS) measurement was used to establish the stability of the surface of the synthesized material to oxidation.The MCS fabricated composite contains Fe 2+ (Fe 2p3/2: 710.65 eV, Fe 2p1/2: 725.79 eV and satellites: 717.76 and 722.39 eV), and Fe 3+ (Fe 2p3/2: 712.72 eV, Fe 2p1/2: 729.2 eV), according to the high-resolution spectrum of Fe2p depicted in Fig.5b32 .The high resolution of C1s shown in Fig.5calso displays four peaks at 284.88 eV, 286.29 eV, 287.74 eV, and 289.57eV, which are associated with C-C, C-N, C-O, and C=O, respectively.Three fitting peaks with respective centers at 399.31 eV, 400.71 eV, and 402.17 eV were identified in the N1s spectrum presented in Fig.5das -NH 2 (primary amine), -NH 3 + (quaternary ammonium), and NHCO, respectively.Here, -NH 2 has a molar proportion of 25.73%, and -NH 3

Figure 6 .
Figure 6.(a) Comparison between control, CS, and MCS in color removal % and turbidity on CJ, (b) Brix°, purity, and pH performance for control, CS, and MCS on CJ.(c) Comparison between control and MCS in color removal % on sugar syrup.(d) Brix°, purity, and pH performance for untreated syrup, control, and MCS.(e) Turbidity curve for untreated syrup, control, and MCS.(f) Flotation rate curves for anionic flocculant dosages against time.

Figure 7 .
Figure 7. Adsorption illustration of colorants using MCS nanocomposite and magnetic field.

Table 1 .
Comparison between control, CS, and MCS on the quality parameters of CJ.

Table 2 .
Comparison between traditional clarification and MCS on sugar syrup.